Proper site preparation requires that the ground be graded as necessary for compatibility with planting, sodding, paving or whatever the next and usually final construction or maintenance step may be. Such site preparation typically involves first breaking up and loosening the soil as necessary followed by leveling the soil to the desired grade. This may entail the use of different tools, depending upon the soil conditions, and multiple passes over the site which is both time consuming and expensive.
In the past weighted boards and the like were dragged behind tractors to smooth and level the surface of the soil. This technique was relatively crude and unsatisfactory because it did not allow for controlling the angle or grade of the soil surface, and loose dirt tended to collect in front of the board which would escape around the outer edges leaving ridges which then had to be smoothed manually with rakes or the like.
My prior U.S. Pat. No. 3,556,228 shows an apparatus for leveling soil and the like which was adapted to overcome the difficulties associated with the prior art at that time. This device generally consisted of a frame adapted for connection to a three-point hitch on a draft vehicle such as a tractor. The frame consisted of a number of transverse ground engaging members arranged in longitudinally spaced apart relationship. The leading member therein was a member of generally inverted U-shaped cross section to effect cutting, while the other trailing members were of closed, generally rectangular cross section for leveling purposes. The transverse ground engaging members were interconnected by longitudinal braces in a ladder-like fashion to form a rigid frame. Individual retaining shoes or plates were provided on opposite ends of each ground engaging member to retain loose soil to avoid formation of soil ridges.
This device operated well and was a significant improvement over the prior art at that time, although experience later showed that improvements could be made. The parent hereof, referenced above, discloses such an improved soil leveling apparatus. It has been found, however, that even this device can be improved upon. For example, under some soil conditions it has been found that the effectiveness of a leading ground engaging member of generally inverted U-shaped cross section can be severely restricted if it should become plugged with soil. In addition, three-point hitches of various types and ages exhibit various degrees of looseness which may not be compatible with different soil conditions. Some degree of play or looseness at the top link of the three-point hitch is generally desirable because it enables the apparatus to float somewhat on the soil surface without undue gouging, however, too much looseness is undesirable.
Further, some conditions may call for soil working relatively less aggressive, but which is desired as a substitute for or in addition to, that type of soil working provided by the scarifier assembly.
There is, thus, a need for an improved soil leveling apparatus of even greater versatility.